The present invention relates to a transfusion pump having a pivotal finger for urging a tube for supplying a liquid in the tube.
A conventional technique disclosed in Japanese Patent Laid-Open No. 61-85593 is known as a conventional transfusion pump having a plurality of pivotal fingers to peristaltically drive the fingers. In this prior art, a pair of projections constituting a fork-like shape is integrally formed at the rear end of each finger to pivot the finger. An eccentric disc cam is clamped between the projections, and the finger is reciprocally pivoted upon eccentrical pivotal movement of the cam.
In this conventional transfusion pump having the above arrangement, however, a predetermined clearance is required between the eccentric disc cam and both the projections in order to allow an eccentrical pivotal movement of the eccentric disc cam. As a result, cluttering occurs between the eccentric disc cam and the finger although it is slight.
When the eccentric disc cam changes its urging direction from a direction to come close to and urge a tube through a finger to a direction to be separated to release the urging force, the finger is not pivoted upon pivotal movement of the eccentric disc cam by a stroke corresponding to the cluttering play. As a result, the liquid in the tube is not appropriately fed in a liquid supply direction, resulting in inconvenience.